检查base64文本是否为有效的RSA公钥(4096)

import base64
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.backends import default_backend

def is_valid_rsa_public_key(base64_public_key):
    try:
        # 解码Base64文本
        public_key_bytes = base64.b64decode(base64_public_key)
        
        # 尝试加载公钥
        public_key = serialization.load_der_public_key(public_key_bytes, backend=default_backend())
        
        # 检查密钥长度
        if public_key.key_size == 4096:
            return True
        else:
            return False
    except Exception as e:
        print(f"Error: {e}")
        return False

# 示例Base64编码的RSA公钥
base64_public_key = "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA..."

# 检查是否为有效的RSA公钥
if is_valid_rsa_public_key(base64_public_key):
    print("Valid RSA public key (4096 bits)")
else:
    print("Invalid RSA public key or not 4096 bits")